Pretreatment with DEX impairs the T-cell stimulatory capacities of DCs activated via CD40.

Allogeneic mixed lymphocyte reaction: nonadherent allogeneic peripheral blood mononuclear cells were cultured with different numbers of CD40-triggered DCs, DEX-treated CD40-triggered DCs, or immature DCs. The proliferative response was measured on day 5. Th1 stimulation assays: Hsp65-specific T cells were cultured with different numbers of HLA-DR matched CD40-triggered DCs or with DEX-treated CD40-triggered DCs, or with immature DCs, pulsed with the hsp65 protein or with the specific p3-13 peptide epitope. The proliferative response and the T-cell dependent IFN-γ production were analyzed on day 3. Data are representative of 3 independent experiments.